Syntax

Description

The mkgrmf program generates an OGIP style RMF appropriate for
spectral analysis of grating observations. The RMF is a
representation of how the incident source photons are
redistributed onto the detector, thus the grating RMF contains
the HRMA + grating line spread function (LSF) vs energy for a given
detector and grating combination.

mkgrmf calculates the RMF on user defined set of grid points,
e.g. wavelength channel, for a given set of input functions. The
output file contains two FITS extensions, MATRIX and EBOUNDS.
The MATRIX is generated by interpolating the parameters of
LSF function in wavelength and then generating the LSF from the
interpolated parameters. The EBOUNDS extension contains an array
with the energy boundaries of each of the detector channels.

The input data files for mkgrmf have a few sets of LSFs per grating
type, order, and detector configuration, a set for each of five to ten
extraction regions. These regions range approximately from the 60 to
99% encircled energy (EE), where the percentage is defined to be at
1.497keV. The user is not required to use any specific extraction
region width; the tool will use a series of interpolations to
determine the best RMF for the extracted data. For the case where the
extraction region is larger (or smaller) than the largest (smallest)
EE region, the RMF will be derived via extrapolation. The region
is, however, required to be centered on the source. If not (as may
be necessary in crowded fields), the EE will not be accurate.

The extraction region is assumed to be appended to the PHA file. For
the grating data processed by CIAO, this region is appended to the
type II PHA file.

Note that the RMF generated is not normalized. Since the EE is
extraction-region dependent, there is a wavelength-dependent
component of the effective area contained in the RMF --- both ARF
and RMF are needed for accurate flux determinations. Default region
widths for HETGS provide 93-98% EE, and for LETGS the EE ranges
from 88-97%.

Computes a third order RMF for the HEG, writes the output to heg3.rmf
and uses the default grids for the rmf. Note setting the parameter
wvgrid_arf to "1.0:21.48:#8192" is equivalent to setting it to
compute.

Detailed Parameter Descriptions

Parameter=outfile (string required filetype=output)

Output File Name

The name of the output RMF file.

Parameter=wvgrid_arf (string required default=compute units=Angstrom)

Enter ARF side wavelength grid [angstroms]

Wavelength grid for the arf specification string. This string may specify
compute, a file, or an explicit energy grid. For example, to use
a grid for the MEG that ranges from 1 to 41.96 angstroms with 8192
channels set. The units for this parameter is angstroms.

Specification string for the channel side wavelength grid. This string
may specify compute, a file, or an explicit energy grid. In general this
is set to be the same as the arf grid. However, there is no compelling
reason that the fitting engine needs the ARF and the RMF on the same grid
so this has been left as a user adjustable parameter. The units for this
parameter is angstroms.

Parameter=order (integer required default=1)

Enter Grating order

The order that the RMF will be computed for.

Parameter=obsfile (string required filetype=input)

Name of FITS file with observation info

The name of a FITS file containing keywords which specify the
mission, detector, SIM offsets, extraction region etc. The PHA2
spectral file is needed to read the width of the extraction region.
The LSF input data files have LSFs for approximately 99.75,
99, 96, 90, and 60% encircled energy, where the percentage is
definted to be at 1.497keV. The tool then interpolates the LSF parameters.

Parameter=regionfile (string required filetype=input)

File containing extraction region

The name of a FITS file containing keywords which specify the
extraction region.

Parameter=srcid (integer required default=1)

SrcID

The number of the source in the spectrum list. This will be used
to determine source parameters such as the source position.

Parameter=threshold (real required default=1.0e-6)

Enter RMF threshold

The lowest value for the response matrix calculation.

Parameter=detsubsys (string required default=ACIS-S3)

Detector Name (e.g., ACIS-S3)

The ACIS chip or HRC plate on which the 0th order falls.
The value of this parameter is passed to ARDLIB to select a
particular detector subsystem so that the appropriate grid can be
computed for the case where wvgrid_arf and wvgrid_chan are both set
to "compute". For Chandra, this is most commonly one of these two
detector subsystems:

ACIS-S3

HRC-S2

However this parameter can be any one of the following detector subsystems:

HRC-I

HRC-S1, HRC-S2, HRC-S3

ACIS-I0, ACIS-I1, ACIS-I2, ACIS-I3

ACIS-S0, ACIS-S1, ACIS-S2, ACIS-S3, ACIS-S4, ACIS-S5

Parameter=grating_arm (string required)

Enter Grating Arm

Name of the grating that the rmf will be computed for. Valid values
are HEG, MEG and LEG.

Parameter=verbose (integer required default=0 min=0 max=5)

Verbosity

The verbose parameter is used to set the level of output from
mkgrmf.

Parameter=diagonalrmf (string default=no)

Compute diagonal RMF

Option to compute a diagonal RMF. This option gives the correct wavelength
grid for any order but has no LSF information encoded.

Parameter=ardlibparfile (string default=ardlib.par)

name of ardlib parameter file

The tool-specific parameter file contains no explicit CALDB
parameters. Instead, the CALDB parameters are all contained in
a separate parameter file selectable using the `ardlibparfile'
parameter; "ardlib.par" is the default file name. Calibration
files are specified implicitly via the `DetSubsys' and `Mirror'
parameters described below.

Parameter=geompar (string default=geom)

The name of the Pixlib Geometry parameter file.

Parameter=mirror (string default=HRMA)

Mirror Name

For Chandra the mirror parameter must be set to
"HRMA".

Parameter=clobber (boolean default=yes)

Overwrite existing files?

The default values here is yes which allows you to overwrite
existing files. Changing this to "no" will prevent the
overwriting of files.

Notes

The command "mkgrmf --version" prints the version of
mkarf and the associated libraries. This is useful when
reporting problems with the tool.